Apparatus for producing artificial filaments



June 19, 1962 E. K. BAUER APPARATUS FOR PRODUCING ARTIFICIAL FILAMENTS Filed May 12, 1958 Unite Ernest K. Bauer, Meadville, Pa.,

Pa., a corporation Viscose Corporation, Philadelphia, of Delaware Filed May 12, 1958, Ser. No. 734,716 4 Claims. (Cl. 18-8) The present invention relates to an apparatus for producing artificial filaments and more particularly artificial filaments having alternating segments of differing characteristics such as different colors.

One of the features affecting the denier of artificial filaments is the pressure and volume of flow of the spinning solution through the orifices of the spinneret or jet. in the past it has been entirely practicable on a commercial scale to produce constant denier filaments in colors but when an attempt has been made to produce filaments having alternating segments of differing colors or alternating segments differing in some other characteristic, great difficulty has been encountered in maintaining the denier of the filaments uniform or constant throughout their length. Part of the difiiculty has been caused by the fact that the methods of production have generally involved a continuous flow of a spinning solution of a particular color and periodically adding to the basic spinning solution a second solution which imparts a different color to the material extruded through the spinneret orifices, and during the periods While the second solution is being added there is an increased flow through the orifices with the result that the filaments are characterized by segments of varied cross-section. Another difficulty encountered in spinning filaments having alternating segments of differing characteristics has been the inability to provide sharp lines of demarcation between the segments.

The present invention overcomes the above-mentioned difficulties by providing a uniform mate of flow of spinning solution or dope to and through the spinneret. In general, this uniform rate of flow is accomplished by providing a main stream of clear or neutrally characterized spinning solution and continuously but alternately injecting into the neutral stream, preferably at a point close to the spinneret, at least two differently characterized additives so that the filaments formed by extrusion of the spinning solution will have alternating segments of differing characteristics. Since one or another of the additives is constantly entering the main stream of spinning solution, the rate of supply of the total spinning solution can be kept uni-form, with the result that the filaments have a uniform cross-section throughout their length. By shutting off one additive stream at the same instant that another is started, sharp lines of demarcation are formed between adjacent segments of the filaments.

It is an object of the present invention to provide an apparatus for spinning uniform denier filaments having alternating segments of differing characteristics such as different colors.

It is a further object of the invention to provide an apparatus for producing uniform denier filaments having alternating segments of differing characteristics wherein there is a sharp line of demarcation between adjacent segments.

Other and further objects, features and advantages of the invention will become apparent as a description of a preferred embodiment thereof proceeds.

Referring now to the drawings:

FIGURE 1 is a plan view of the apparatus, and

FIGURE 2 is a sectional view I-I-II of FIGURE 1.

The apparatus shown in the drawing is particularly adapted to the spinning of acetate filaments but it will be taken along the line tates atet 3,9331% Patented June 19, 1962 understood that such apparatus may be modified in known ways to adapt it to the spinning of viscose or any other material which may be spun by presently known wet, dry or melt spinning techniques and that the method of the present invention is likewise adaptable to the spinning of a wide variety of materials which may be spun by these various techniques.

In the drawing only one station of the spinning machine is shown but it will be understood that in practice there are a large number of such stations. At each station a circular disk-like member 10 is suitably secured to the framework 11 of the machine. The member 10 is provided with a central opening w'thin which is secured a. fitting 12 having a central bore 13 which, as shown in FIGURE 2, has a larger diameter at the top portion than at the bottom "and said fitting is also provided with a pair of horizontally extending bores 14 and 15 which communicate with the smaller portion of the central bore 13. Bolts 16 and 17 are screwed into the fitting 12 and lock nuts, such as indicated at 18 in FIGURE 2, serve to hold the fitting tightly in place. A main conduit 19 through which a colorless or neutrally characterized spinning solution is forced under uniform pressure and volume of flow has Welded to the end thereof a flange 20 by means of which said conduit is secured by the bolts 16 and 17 in axial alignment with the bore 13 of the fitting 12. A jet or spinneret 21 is secured to the fitting 12 by means of a flanged collar 22 and a coupling 23, the latter of which is provided with a central bore 24 aligned with the bore 13 so that spinning solution passing through the bore 13 will be conducted to the space back of the face of said spinneret through the orifices of which it will be extruded to form filaments.

A member 25 is secured to the fitting 12 by means of a flange collar 26 which screws onto a threading portion of said fitting and said member is provided with a bore 27 aligned with the horizontal bore 14 and with a bore 28 aligned with the horizontal bore 15. Secured to the member 25 are a pair of additive injection devices generally indicated at 29 and 30.

The injection device 29 comprises a cylindrical member 31 having a large axial bore 32 in the upper portion thereof and a smaller axial bore or cylinder 33 in the lower portion thereof, a port 34 serving to place the cylinder 33 in communication with the bore 27 of the member 25. A piston 35 operates within the cylinder 33 and said piston has an operating head 36 slidably guided within the enlarged bore 32. A spring 37 mounted in the bore 32 urges the piston in a downward direction. Screwed into the side of the cylindrical member 31 is an element 38 having a bore 39 which communicates with the cylinder 33 and leading to this element is a conduit 40 for conducting a first supply of a suitable additive, such as a dye. Spring urged ball valves 41 and 42 in the bores 27 and 39, respectively, control the flow of additive through these bores. Thus, as the piston 35 rises, the valve 42 opens to admit additive into the cylinder 33, the valve 41 being simultaneously closed due to the reduced pressure within the cylinder 33. As the piston 35 moves downward the increased pressure within the cylinder 33 causes the valve 42 to close and the valve 41 to open so that the fiuid within the cylinder 33 will be forced through the bores 27 and 14 and into the main stream of spinning solution.

The injection device 30 is similar in construction to the injection device 29 and comprises a cylindrical member 43 having a small bore or cylinder 44 in the lower portion thereof and an enlarged bore 45 in the upper por tion thereof. A piston 46 operates within the cylinder 44 and said piston has an operating head 47 which works within the enlarged bore 45. An element 48, to which is connected a second additive supply line 49, is secured to the cylindrical member 43 and is provided with a bore 50 in communication with the cylinder 44. Upon upward movement of the piston 46, a quantity of additive is drawn into the cylinder 44, a spring urged ball valve 51 within the bore 50 opening due to the reduced pressure to allow the additive to enter said cylinder. Upon downward movement of the piston 46, the valve 51 is closed and a ball valve 52 within the bore 28 is forced open to allow the additive contained within the cylinder 44 to be discharged into the main stream of spinning solution, a port 53 through the wall of the member 43 placing said cylinder in communication with said bore.

The injection devices 29 and 30 may be characterized as positive displacement pump means and in order to operate them alternately the operating heads 36 and 47 are operatively interconnected by a rocker member 54 which is pivotally mounted upon a stud 55 carried by a flange 56 secured to the framework 11. One arm of the rocker member 54 extends through a slot in the upper portion of the cylindrical member 31 and through a slot 57 in the operating head 36 of the piston 35. The other arm of the rocker member extends through an elongated slot in the cylindrical member 43 and is cooperatively engaged within an opening 58 provided in the operating head 47 of the piston 46. The main drive shaft 59 of the machine, which operates the pumps supplying spinning solution to the various lines 19 at the different spinning stations, is provided with a cam 60 which engages an operating portion 61 of the rocker member 54, the spring 37 of the injection device 39 serving to hold said operating portion in engagement with the surface of said cam.

It has previously been mentioned that in order to produce filaments having a uniform denier throughout their length it is necessary that the volume of flow of spinning solution to the spinneret be maintained at a constant value. Thus, the pivot 55 is located midway between the two injection devices so that the pistons of each of them will be moved through the same stroke and the diameters of the cylinders 33 and 44 are the same so that each injection device forces the same quantity of additive into the main stream of spinning solution. Since the operating elements of the injection devices are interconnected by the rocker member 54, one or the other of them is continuously being moved through its operating stroke at the same time that the other is being moved through its return stroke. Thus, by continuously injecting constant amounts of additive and by maintaining the flow through the main conduit 19 at a constant value, as previously mentioned, the total supply of spinning solution to the spinneret is maintained at a uniform rate.

While the total volume of flow to and through the spinneret is maintained constant so as to produce filaments having a uniform denier, the filaments will be characterized by alternating segments of differing characteristics since, as previously mentioned, the two additives supplied through the lines 40 and 49 have different characteristics. The material to be injected into the main stream of spinning solution may consist of a slurry of spinning solution similar to the main spinning solution and some material giving the spinning solution a special characteristic such as some particular color or the injected materials may be merely two diiferent dyes which impart different colors to the main stream of spinning solution.

By locating the points of injection close to the spinneret and sharply stopping the flow of one of the additives at the same instant that the flow of the other is started, it is possible to produce sharp lines of demarcation between the differently characterized segments of the filaments. It should also he mentioned that as shown in FIGURE 1 the bores through which the two additive supplies enter the main stream are placed out of alignment with one another so that the additives will enter entirely into the main stream and not be injected into the passageways or bores reserved for the other additive.

Having thus described the invention, what is claimed is:

1. Apparatus for spinning uniform denier filaments having alternating segments of differing colors comprising a supply of clear liquid spinning dope, a spinneret through which said spinning dope is extruded to form filaments, a conduit leading from said supply of clear liquid spinning dope to said spinneret, a pair of positive displacement pump means having discharge ports communicating with said conduit at points close to said spinneret, means for feeding a differently colored liquid additive to each of said pump means, and means for continuously operating said pump means in sequence whereby one or the other of the colored additives is constantly being discharged into said conduit so that the total amount of spinning liquid supplied to the spinneret is maintained at a uniform rate.

2. Apparatus for spinning uniform denier filaments having alternating segments of differing colors comprising a supply of clear spinning dope, a spinneret through which said spinning dope is extruded to form filaments, a conduit leading from said supply of clear spinning dope to said spinneret, a pair of positive displacement pump means having an operating stroke and a return stroke and having discharge ports communicating with said conduit at points close to said spinneret, means for feeding a differently colored spinning dope to each of said pump means, means operatively interconnecting said pump means to cause one of them to move through its return stroke whenever the other moves through its operating stroke, and a drive for the last-mentioned means for continuously operating said pump means in sequence whereby one or the other of the colored spinning dopes is constantly being discharged into said conduit so that the total amount of spinning dope supplied to the spinneret is maintained at a uniform rate.

3. Apparatus for spinning uniform denier filaments having alternating segments of diifering colors comprising a supply of clear spinning dope, a spinneret through which said spinning dope is extruded to form filaments, a conduit leading from said supply of clear spinning dope to said spinneret, a pair of positive displacement pump means having an operating stroke and a return stroke and having discharge ports communicating with said conduit at points close to said spinneret, means for feeding a differently colored spinning dope to each of said pump means, valve means in each of said pump means to prevent leakage of colored spinning dope into said conduit during the return strokes of said pump means, means operatively interconnecting said pump means to cause one of them to move through its return stroke whenever the other moves through its operating stroke, and a drive for the last-mentioned means for continuously operating said pump means in sequence whereby one or the other of the colored spinning dopes is constantly being discharged into said conduit so that the total amount of spinning dope supplied to the spinneret is maintained at a uniform rate.

4. Apparatus for spinning uniform denier filaments having alternating segments of differing characteristics comprising a supply of neutral spinning dope, a spinneret through which said spinning dope is extruded to form filaments, a conduit leading from said supply to said spinneret, means for forcing said spinning dope through said conduit under pressure, a first injection apparatus for injecting an additive into said conduit near said spinneret, said apparatus comprising a cylinder and piston, a valved port through which a first additive is introduced into said cylinder, a valved port leading from said cylinder to said conduit and through which said additive is ejected when said piston moves into said cylinder, a sec ond injection apparatus similar to the first for injecting References Cited in the file of this patent UNITED STATES PATENTS Allen et a1. Jan. 3, 1939 Manis Apr. 11, 1950 Braunlich Dec. 3, 1957 Lavash Feb. 11, 1958 

